It seems like only yesterday that Bob Irwin was just a blonde bowl-cut cutie, but in the blink of an eye, the budding animal activist and photographer is all grown up!
Marking his 13th birthday with his first Instagram post, the son of the late Steve Irwin shared a video to celebrate the occasion.
One of the first to congratulate Bob on becoming a teenager were Rove & Sam – who posted a picture to their Instagram of an excited Rob holding a birthday cake in the shape of a dog.
'A MASSIVE happy 13th birthday to this little legend Robert Irwin! We hope you have the best day ever!' the caption read.
His sister Bindi was also quick to wish her brother happy birthday – sharing an adorable throwback picture and making sure to remind her 1.3 million followers that Bob is now on instagram.
‘Happy Birthday to this amazing human being, my brother 💛 Today you turn 13 and I am so proud of you. This photo was taken many years ago, I still can't believe that today you're a teenager. Since the first day I met you, when you were born, I knew you were destined for great things. You inspire me every day. I love you. Ps. You now have Instagram! @robertirwinphotography’
Bindi's boyfriend, Chandler got in on the act - sharing a photo of the trio.
Happy birthday @robertirwinphotography You're the best photographer I know and congratulations on joining the Instagram world! Have the best birthday, can't wait to celebrate with you @australiazoo Thank you for all the awesome Zoo Tours.
Bob’s mum Terri also tweeted a heartfelt message to her son.
'While my heart aches that Steve isn't here for Robert's 13th birthday, each day I'm more aware that Steve lives on thru his incredible son,' she wrote alongside a picture of her late husband and Bob as a baby.